The Dillon tribune., 1887-04-01
Gle 1iNon EHbmr.
PHOIDJIFIC WORK.
SOMETHING kCCUT THE VARIOUS
PROCESSES NOW EMPLOYED.

ooMETHiHG kCCUT THE VARIOUS
PROCESSES NOW EMPLOYED.
Tho Methods of GouriI. in F:r:s-Cuic',.
ness of American prorcsscs--1Lc Ac.
ton Of Light on scnsitizch Gclatins.
pl,otn,r:..rrc.
The ni,s1 common forms Of reproductive
urt How:t q; are those hac"i On photcr-
rnphy and il may not DC generally known
that the I.lost c:tensiSc concern in the
country t,at is devoted to t.,i.s kind Of
work is housed in Eroolslyn. The corl-
pnny who cont rolls these WORKS and rive
employment to !, considerable nti;nbcr of
operatives. some Of Wlio.l are to be re-
gardc1 a. artists rather Chan mechanics,
for into the inis.l."t; and printing cf TIC
plates taste rs well rs si.ill l,u&t enter.
The house Of Golpii, in Pari;, has until
recent years enjoyed almost IL monopoly
Of phrtcsrayErc, and il; v;oi,. has Celeb
rity for strcn"t!l and clcC;rcs3. The
Goupil process is d secret. bot it is cvi-
dent from the length OF time taken to
prepare II plate, and iror, t,c Up, c"r;::.cc
Of sundly lines and n,;.rliia'-; That would
not .,;Tonly ,hov in u solar rri:h, that
hand WORK IS rc&s!y cs important /, fac
tor rs c.ici !.cal evolution. I'ilc company
hero in Brooklyn finishes Il rl@tc l.. IS
many Enuri ca GayS are t:;.cl ~ tac
GOupil iirHl, am! tho results arc in man,
instances t',rnrignc. Adynnces il. t.!e
art nrc still to be made, lt.t itcra is u
broad foundation tov'ori: upward from.
There &re dozens CT ral;cs fer what is
substantially the SAL rroc2s,3--tl.c p,,cto-
type, photoprint, iaoastyuc, albertygc,
artotypA l'chtiru';, l;ni;"typc, caruon
print, artcgiyp'', I've; process, Elciac.-
bach process, raoto lit,loCra, i, lActo
cau2t;c print, photo mcl:.tiac l.'gt, Photo
cngrt"iaT zinc ctc':ing c~n I,1ctorra-
vurc. The action of ii,,'t Gil IN ;,.:cd
gcl"ti,.c Or other ln.icIicl i; the occasion
of al these fcrl.a. G2l3tinc 3, made SEN
sitiyc by treatment with Hichr"- ate &C :
potash, "iiic., likewise renders IL in&ol- |.
nblc hy water, and i'll thij cuuHi5.on il f,
viii st: '.c' grease, w.lcn taat t. a2plc,l, |
but when sclGtiEc 'lcct Is j.l"cct, under
u Photographic negative TIC effect CT lci!t |
stri!snt; t.roug'i tac .sl;2.r:; is to c!c3o to |
pores Of tho gclatinc clNl harden il. AID !
where light does not Cct the :,cl:tuc Ec-
comes soft and absorbent. After tho
sheet has received tic irlrrccn from tic
negative IL greasy ink will adhere TO the !
hard portions, while the sponge areas,
being kept moist with water refuse it.
You apply Your ink, lay piece of rsrcr
on 1t, stamp it, the ink comes oil u.l The .
paper and there is your picture, hello
type, in commercial Phrase. |
APPLIED TO STONE PRINTING:
This process is 1luch the ;a,:,c as lit..
ograply, but the li,.!oyrnrlic stone holds
grease only where there are decided l.ncs,
while gclatinc receives tho impress CT II
hundred gr!tatons Of light and shade.
photography is applied to stone printing
where anything is to be represented by
cleln masses Of black and white, and il is
therefore useful for copying ElGrs, plans,
tracings, ink drawings, designs. miniature
calendars, papers and catalogues, line cn.
cravings, autograph letters, ana so on.
In that case paper coated with ~r!ut.Ec is
printed on by u negative, as in the eases
OF IN ordinary photograph, ard the grease
taking lines arc transferred bodily to the
stone. When the ink lines nrc transferred
to zinc instead Of stone and the exposed
portions OF tho metal arc eaten down by
acid, leaving tho lines in relief, rlate il
made that is similar to ~ stereotype, end
shis lor'l Is commonly used for cheap H.
iustrat:ons In daily papers. a plaster
cast may tx taken from IL Eclatinc i'm.
press after the Lines hayo set, and frcm
this may ]" made n metal plate That will
print what nrc called photo cngravincs.
For photogravurc biclromatixy,l ,,cla.
tino is mixed with sanl or emery dust. tic
picture Is thrown on it from u negative.
the grease taking lines harden, the light
portions nrc swollen with water and
copper shell is deposited on it Us un c ..cctru-
type. Tho sand gives II Grain to the sur.
lace md holds tho ink where it is ,icsi,.
aole to imrart u half tint. In the hands
oi sE'l'tul printer II proof photosr.v,re
can oe made almost as stron,, Es ap etcl.
ing, rs it is easy to wipc out tho lich
lights until they nrc represented by the
actual whitcncss Of tho PAPER thct re.
cclvcS TIC print, while tones and masses
OF Shallow ere obtainablc by leaving iilc.s
M ink of less or greater density on tho
metal surface. ce.---Erooklyn l.aylc.